Improved corrosion resistance and magnetic properties of Nd‐Fe‐B‐type sintered magnets with Mo and Co

1991 ◽  
Vol 69 (8) ◽  
pp. 5844-5846 ◽  
Author(s):  
Satoshi Hirosawa ◽  
Shuji Mino ◽  
Hiroyuki Tomizawa
Keyword(s):  
Magnetic Properties ◽  
Corrosion Resistance ◽  
Sintered Magnets

The Effect of Niobium and Boron Content on Magnetic Properties and Corrosion Resistance of Pr-Fe-Co-B-Nb HD Magnets

2008 ◽  
Vol 591-593 ◽  
pp. 96-101
Author(s):  
J.D. Angelo ◽  
C.C. Motta ◽  
Luzinete Pereira Barbosa ◽  
Hidetoshi Takiishi ◽  
Isolda Costa ◽  
...  
Keyword(s):  
Magnetic Properties ◽  
Corrosion Resistance ◽  
Boron Content ◽  
Permanent Magnets ◽  
Magnetic Behavior ◽  
Optimum Amount ◽  
Sintered Magnets

The hydrogenation decrepitation process was employed to produce sintered magnets using a mixture of two alloys. The effect of niobium and boron content on the magnetic properties of Pr14FebalCo16BxNby-type sintered magnets was studied. Niobium and boron have a significant effect on the magnetic behavior of these permanent magnets. The optimum amount of boron was 6 at% and niobium should be kept below to 0.50 at%. The squareness factor (0.90) has been improved considerably and good overall magnetic properties (Br=1320 mT, iHc=700 kAm-1 and (BH)max=315 kJm-3) have been achieved for the sintered magnets prepared from the Pr14Fe63.85Co16B6Nb0.15 alloy.

Microstructure and magnetic properties of core-shell Nd-La-Fe-B sintered magnets

2018 ◽  
Vol 749 ◽  
pp. 580-585 ◽  
Author(s):  
Jiaying Jin ◽  
Zheng Wang ◽  
Guohua Bai ◽  
Baixing Peng ◽  
Yongsheng Liu ◽  
...  
Keyword(s):  
Magnetic Properties ◽  
Core Shell ◽  
Sintered Magnets ◽  
Microstructure And Magnetic Properties

Interaction mechanism, magnetic properties and microstructure of Ce-Fe-B/Alnico spark plasma sintered magnets

2021 ◽  
pp. 168237
Author(s):  
Sajjad Ur Rehman ◽  
Qingfang Huang ◽  
Rizwan Ur Rehman Sagar ◽  
Qingzheng Jiang ◽  
Munan Yang ◽  
...  
Keyword(s):  
Magnetic Properties ◽  
Interaction Mechanism ◽  
Sintered Magnets ◽  
Spark Plasma

Effect of Electrolyte Composition on Corrosion Resistance in Nickel Plating Process for Coating Bonded Magnet PrFeB

2014 ◽  
Vol 896 ◽  
pp. 245-248 ◽  
Author(s):  
Candra Kurniawan ◽  
Hayati M.A. Sholihat ◽  
Kemas Ahmad Zaini Thosin ◽  
Muljadi ◽  
Prijo Sardjono
Keyword(s):  
Magnetic Properties ◽  
Corrosion Resistance ◽  
Corrosion Rate ◽  
Nickel Coating ◽  
Electrolyte Composition ◽  
Nickel Metal ◽  
Sem Images ◽  
Average Value ◽  
Immersion Corrosion ◽  
Bonded Magnet

Despite of its excellence magnetic quality, one of the critical properties of PrFeB based permanent magnet is a low corrosion resistance so it can be oxidized easily which can reduce its magnetic properties. In this study, Nickel coating has been performed for bonded PrFeB magnet by the electroplating method using Nickel-Watts bath-type as the electrolyte to improve the corrosion resistance. The varying amount of the electrolyte compounds used to have the optimized composition indicated by the corrosion resistance measurement. The solution composition used was NiSO4 (230-380 g/L), NiCl2 (30-60 g/L), and H3BO3 (30 and 45 g/L) with a fixed value of other parameters. Characterization used including the immersion corrosion test, microstructure analysis, and magnetic properties. Based on the corrosion rate measurement, the highest corrosion resistant of Nickel coated PrFeB magnet achieved from the electrolyte composition of NiSO4: NiCl2: H3BO3 = 380: 60: 30 g/L with a plating time and current density (J) of 60 minutes and 40 mA/cm2 respectively. The corrosion rate data showed that the Nickel metal coating can improve the corrosion resistance of bonded PrFeB magnet up to 29 times than of the substrate. The SEM images showed that the thickness of the Nickel coating on the optimum electrolyte composition was in average value of 35.1 µm. The overall samples has a magnetic remanence value (Br) reached ≥ 6 kG, so it has enough properties to be applied in devices such as generators and electric motors.

Sign in / Sign up

Export Citation Format

Share Document